Comparison between the supply index values of domestic materials and the WPB standard values
Although from a standard perspective, it seems that domestic materials cannot replace WPB, we can still find some conclusions with practical substitution value based on the actual supply value of domestic materials. From the previous analysis, there are two main aspects that affect the establishment of substitution:
The issue of Si content in Q series steel plates;
⑵ All domestic material performance standard indicators are lower than the standard requirements of WPB.
By comparing Table 3 and Table 4, we can see that:
The actual supply value of SI content in Q series steel plates is between 0.13-0.22%, which meets the requirement of WPB SI ≥ 0.1%.
⑵ Domestic materials
The actual supply values of performance indicators for 20 # and 20G steel pipes are: Ts is 420-550Mpa, Ys is 250-350Mpa, and elongation EL is 24% -38%, HB is 145-185 (according to actual measurement, the hardness of the pipe fittings is basically consistent with the hardness of the raw materials), and all the performance strength index values of the tested furnace numbers meet the requirements of the WPB standard; ⑶ The actual supply value of performance indicators for domestically produced Q235A and Q235B steel plates: Ts is 405-495Mpa, of which only two furnaces are less than 410Mpa (lower than the WPB requirement), accounting for 0.8% of the total furnaces; Ys is 255-360Mpa, which meets the requirements of WPB; The elongation EL is 25% -37%, which meets the requirements of WPB; HB is 140-170 (according to actual measurements, the hardness of the pipe fittings is basically the same as that of the raw materials), which meets the requirements of WPB.
Conclusion:
By comparing the chemical composition and mechanical properties of domestically produced GB8163-20 # and GB5310-20G seamless steel pipes, as well as GB3274-Q235A and Q235B medium thick plates, with ASTM A234GR The comparison between standard specifications and actual supply values of WPB shows that within the range of furnace batches, 100% of domestically produced carbon steel seamless steel pipes can comply with ASTMA234Gr WPB's requirements; More than 99% of domestically produced carbon steel plates in the market can comply with ASTMA234Gr WPB's requirements. By selectively controlling the composition and performance indicators of the purchased raw materials, the use of domestically produced carbon steel materials can fully meet ASTM A234Gr WPB requirements.
ASTM A234 carbon steel pipe elbows are widely favored for their flexibility. 90 degree and 45 degree elbows are standard elbows, but other angles or bends can also be produced by cutting them into different angles.
Two bends with different radii were also used, namely short radius and long radius. The diameter of a short radius elbow is 1, while the diameter of a long radius elbow is 1.5D.
